Seizures (fits): Symptoms, diagnosis and treatment

What are seizures?

A seizure, also known as a fit, is caused by a disturbance in the electrical activity of the brain, which can be due to conditions such as epilepsy.

A person having a seizure may not show any obvious symptoms, but in serious cases they may lose consciousness or experience convulsions. Seizures usually begin suddenly but are often different in their duration and severity.

A person may have one seizure and no further symptoms, or they may have further seizures.

Types of seizure

There are 2 main types of seizure:

Generalised seizures involve both sides of the brain from the start of the attack. Common subtypes include tonic-clonic (grand mal) and absence seizures (petit mal). Febrile and infantile spasms are two types of generalised seizures that occur almost exclusively in young children.

Partial (or focal) seizures are the second major seizure type. These begin in a specific area of the brain and may be contained there. Or they may spread to the entire brain.

With simple partial seizures, the person remains conscious.

Complex partial seizures involve impaired consciousness.

What causes seizures?

Often the cause of a seizure is unknown. Many conditions can provoke seizures, including:

What are the symptoms of seizures?

Symptoms of seizures vary widely, depending on the part of the brain affected by the electrical misfiring. If a very small part of the brain is affected, you might sense only an odd smell or taste. In other cases, you could have hallucinations or convulsions, or you could lose consciousness.

Generalised tonic-clonic: This is sometimes preceded by an aura (awareness of a strange odour, taste, or vision). You might lose consciousness and fall, and experience muscle rigidity (stiffness) or convulsions (jerking movements of the arms and legs). You might also lose bladder control or bite your tongue. After regaining consciousness, you might feel confused and fall asleep.

Generalised absence: This involves loss of awareness and blank stares or eyelid fluttering for up to 20 seconds. You feel well enough to resume activity immediately after the seizure.

Simple partial: Although you don’t lose consciousness, you have involuntary movements, sensations, or psychic experiences such as awareness of a smell or a sense of déjà vu lasting several seconds.

Complex partial: Initial disorientation is followed by strange movements of the arms or legs or odd vocalisations for one to three minutes, as well as loss of consciousness.

Jacksonian: Muscle twitching begins in a single area and then progresses, for example, from the hand to the arm.

Febrile: Preceded by fever in young children, these seizures can be very brief tonic-clonic type seizures or partial seizures lasting more than 15 minutes. Most children who have a fever-induced seizure never experience a second seizure.

Infantile spasms (West Syndrome): Lasting just a few seconds, bending of limbs, neck, and torso while lying down may occur often during a single day. This usually only strikes children younger than three, often those with developmental delays or disabilities.

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